Storage tank



Aug. 18, 1931. G, T, HRTQN 1,819,418

STORAGE TANK Filed May 25. 1928 miumxllnmilmlluli Huwuu'm Patented Aug. 18, 1/931 UNITED STATES lrxrEN'lf 'OFFICE GEORGE T. HORTON, 0F CHICAGO, ILLINOIS STORAGE TANK Application led May 25, 1928. Serial No. 280,509.

'or eliminate evaporation of liquid at the periphery of the tank.`

Another feature of my invention is the provision of means for insulating the wallfof the tank.

Other features and advantages of my invention will appear more fully as I proceed with my specification. Y

In that form of device embodying the fea tures of my invention shown in the accompanying drawings, Fig. 1 is a vertical seotional view and Fig. 2 is a similar fragmentary view on an enlarged scale.

. As shown in the drawings, the tank includes a shell with a vertical wall or walls made of sheet metal or other suitable material and having a bottom 11. The tank is preferably cylindrical, although it is obvious that it may be square, rectangular, polygonal, or any other desired shape. Hereafter, in the specification, I shall describe the device as if cylindrical.

l2 indicates in general the floating roof which floats on the oil 13, or other liquid stored in the tank and moves upwardly and downwardly verticallv in accordance with the volume of oil in tlie tank. 14C indicates a cylindrical curtain concentrically supported inside of the shell and spaced therefrom to leave afn annular space 15 between the wall of y the shell and the curtain surrounding the y tank. The curtain may be made of any suitable material and should have a certain amount of llexibility and resiliency. For example, the same may be made out of relatively thin sheet steel.

The roof 1Q may be of any suitable construction adapted to float on the oil 13.V I have here shown the same as comprising a circular pontoon 12a carrying at its upper inner edge the diaphragm or crown sheet 12". 50

This crown sheet I have here shown as made with some fullness so that the same may flex upwardly and downwardly in accordance with ychan es in the volume in the vapor space 13a a ove the oil and inside of the pon- 55 toon. In Fig. 1 the diaphragm 12b is Shown in its upper position in broken lines and in its lower position in solid lines.

Any suitable means may be provided for making a seal between the edge of .the loating roof and the curtain 14. There are different forms of such seals well known in the art and anyone of the same may be used. Merely for example, I have here shown such a seal as consistin of a flexible tubular mem 75 ber 16 which is a apted to conform in thickness more or less to the space'between the edge of the roof and the curtain 14. With any kind of seal that is used, however, there is more or less diliculty experienced in keeping so the joint between the roof and the wall of the tank perfectly sealed. If the material used for the seal is too soft and com'pressble the same deteriorates and does not wear well.

If stiH material is used, such as metal shoes,

there is more or less difficulty experienced in keeping the same in contact with the wall of the tank throughout the periphery of the roof. Where the seal is directly against the wall of the tank, it will be seen that since the tank wall is made of relatively heavy and sti material it is dillicult to make the same smooth. It is also impossible'to make such tank wall change in shape to conform at all times to the shape of the roof during its vertical move- 9a ments. One of the principal features of my ble material. It is relativel easy to make a good seal between the perip ery of the roof and such a curtain. Such a curtain being of thin material, may be made much smoother than the wall of the tank and it will also change its shape and conform to the shape of the roof during its movements.

The space between the curtain 14 and the wall of the tank 10 is filled with some suitable liquid, for example, water or brine, preferably heavier than the oil stored in the tank, and the bottom of the curtain 14 is provided with some ports 148L to afford communication between the space 15 and the bottom of the tank. By providing the water or other liquid 17 in the space 15, the pressure on both sides of the curtain-14 is equalized thus permitting the use of a relatively thin flexible material for such curtain. In using water -17 or other liquid heavier than the oil 13, there is also provided a liquid seal so that oil does not enter in the space 15 and consequently the same is not exposed to the atmosphere in this space. There are preferably provided ports 18 at the top of the space 15 opening to the atmosphere.

The curtain 14 may-be supported in any l suitable manner. I haveA here s own the same as hanging from a channel iron 19 attached to the inner edge of the tank wall 10. The lower edge of the curtain 14 is preferably attached to the bottom of the tank as by means of an angle iron 20. c

It will be noted that the liquid 17 in the space 15 and the double wall of the tank afforded by the shell 10 and the curtain14 serve to insulate the tank.

While `I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modilications, Changes, therefore, in 'the construcltion and arrangement may be made without in my invention as broadlyas possible in view of the prior art.

What I claim as new, and desire to secure by Letters Patent, is:

1. A storage tank including; an outer shell a yieldable inner shell of relatively light sheet metal spaced therefrom andextending substantially to the'tank bottom; a fluid passage between the space bounded by the inner shell and the space between the shells to equalize the pressure on both sides of the inner shell; and a roof havin a sealing contact with the inner shell adapted to float upon liquid therein.

2. A storage tank as claimed in claim 1,

having a sealing liquid in the space between the shells.

3. A storage tank "as claimed in claim 1,

in which the inner shell has its lower edge attache-d to the tank bottom. 

